A Chinese character is a logogram used in writing Chinese. A complete writing system in Chinese characters appeared in China 3200 years ago during the Shang dynasty, making it what is believed to be the oldest “surviving” writing system. Because the logograms used in writing Chinese are predominantly pictographs, the linkages to the modern Chinese writing system may be decipherable by linguistic archaeologists. Consequently, because thousands of different logograms are used in Chinese, it is difficult to enter Chinese using a computer keyboard.
Once way to represent Chinese characters is to use a “Pinyin” (where “pin” means “spell” and “yin” means “sound”). Pinyin is a way to represent Chinese characters and express the sounds in the Chinese language using the Roman alphabet. There are other systems to express Mandarin Chinese, but pinyin is the most accepted and widely used. Once learned, a person who has learned pinyin will know how to pronounce any word in Mandarin using a Chinese dictionary. Pinyin is also the most common way to input Chinese characters into a computer. Although pinyin and English both use the Roman alphabet, many letters are not expressed with the same sounds that English uses.
Furthermore, words expressed in pinyin use a set of 21 sounds representing the beginning of the word called initials, and a set of 37 sounds representing the end of the word called finals. These combine to form about 420 different sounds. For example, the word for “Flower” expressed in pinyin is “huā”. In this word, the letter “h” is the initial and “uā” is the final. In addition, words are often combined to form compound words. For example, the word for “China” expressed in pinyin is “zhōngguó”. Zhōng means middle (initial: “zh”, final: “ōng”) and guó means country (initial: “g”, final: “uó”).
Moreover, words in Mandarin that have the same pronunciation can have different meanings depending on how the word is said. The “tone” of a word in Chinese describes how the pitch of the speaker's voice changes as the word is said. There are four “tones” in Mandarin. The tones are represented in pinyin by marks above the words.
On a conventional computer with a QWERTY keyboard, there may only be phonetic or pinyin input processes for Chinese input. With conventional pinyin input processes, however, users have no way to input Chinese characters if they don't know the pinyin or if there is no pinyin assigned to a specific Chinese character.